Do-It-Yourself Kit

Rs. 2,789

Rs. 2,511

Includes complete hardware with plain PCB and a pre-programmed controller for building the project. Extensive documentation for project execution including step-by-step instructions for Circuit building, Assembly procedure and Troubleshooting. Thorough understanding from the Problem definition to Circuit Design to Programming, Testing, Troubleshooting and finally building a working hardware project.

Tool Kit

(Recommended)

Rs. 350

Includes Digital Multimeter, Soldering Iron, Screw driver, Cutter, to be used with Do-It-Yourself Kit to build the project.

Loaded and Tested PCB

(Optional)

Rs. 1,099

Rs. 990

Pre-soldered and tested PCB. Choose this option only if you are short on time. Only works along with the Do-It-Yourself Kit. (Can be purchased later)

A time-delay based relay is a relay that stays on for a certain period of time once activated. This circuit is made up of a simple adjustable timer circuit that controls the actual relay.

The time is adjustable from 0 to few seconds, but can be increased by increasing the time constant of the mono-stable 555-timer. The current handling capacity of the load is limited by the kind of relay used. The project is offered with a lamp as a load.

A: The principle behind the project is using 555-timer with RC time constant

Q: What is time delay based relay operated load?

A: It is controlling the switching of load, as per the time decided by the RC time constant of the 555 timer.

Q: What is the formula for calculating smoothing capacitor value?

A: There is some approximated formula .Peak to peak ripple voltage = Load current in amps / (2*line frequency in hertz *capacitance in farads). But as rule of thumb for 1 A current 1000uF is best. Thus it is load dependent.